How the Missing Middle May Help Create Affordable Housing

2.6.2019

By: KIMBERLEE STAFFORD

As discussed in my previous blog post, we need to find ways to build more housing if we are to make a dent in our affordable housing crisis. One solution being explored this legislative session, and by Portland City Council, is to end the ban on so called missing middle homes (duplexes, triplexes, and quadruplexes) in cities.

First some background: prior to 1924, Portland did not have a zoning plan, so any given neighborhood could have a mix of single family homes, duplexes, triplexes, and apartment buildings. Think of Northwest Portland and its mix of housing types.

In the 1920s, the White House convened a task force to push cities to adopt zoning codes. Official documents did not mention race, but the members of the task force were outspoken segregationists, and zoning was seen as a method to keep certain neighborhoods white by keeping the price of homes high. For an excellent discussion of the effects of this government-backed segregation effort, I highly recommend Richard Rothstein's The Color of Law.

The result in Portland was to ban attached homes in neighborhoods like The West Hills, Irvington, Alameda, Laurelhurst, and Eastmoreland, among others. In 1959, that ban was expanded to almost every Portland neighborhood. And the lingering result is that housing costs for the single family residences in these neighborhoods are too expensive for all but the most wealthy Portlanders.

In a city like Portland, where it is not possible to grow out because of our Urban Growth Boundary, much of the cost of housing is tied up in the cost of land. To make housing more affordable, you need to build more densely than a single home on a 5,000 square foot lot. That's the impetus behind Representative Tina Kotek's HB 2001, and Portland's Residential Infill Project, both of which would end the ban on middle housing in most Portland neighborhoods.

The Residential Infill Project has been in the works for over two years. The Project would allow ADUs, duplexes, triplexes, and, in some cases, quadruplexes to be built in R2.5, R5 and R7 zones. The latest model indicates that if the Project is enacted, over 20 years, 24,450 new units of housing will be built, with only 117 more homes demolished compared to if no change is made to the zoning code.

That second number is almost as important as the first, because the chief criticism of the Project by some is that it would result in too many demolitions, causing too much change in Portland's single family residential neighborhoods. The Project is expected to be presented to the City Commission for a vote this spring.

HB2001 would have a similar effect in cities with over 10,000 residents and counties with over 15,000 residents within their urban growth boundaries. HB 2001 would require such cities and counties to allow middle housing (defined in the bill as duplexes, triplexes, quadruplexes, and cottage clusters) somewhere in all residential urban zones. It doesn't require that each type of housing be required in all parts of the zone, just that each zone allows such housing on at least some lots in that zone. The bill has its first hearing on February 11, 2019.

As we continue to struggle with our housing shortage, diversifying our housing supply by allowing housing types that more people can afford is an important piece of solving the affordable housing crisis. Both the Residential Infill Project and HB2001 attempt to do just that by allowing more housing units to be built on land that would otherwise only serve as a single home.